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Retirement Plans And Other Postretirement Benefits (Narrative) (Details) - USD ($) $ in Thousands |  |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Oct. 31, 2023 | Feb. 09, 2022 | Dec. 31, 2023 | Sep. 30, 2023 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |
Pension settlement loss |  |  | $ 66,700 | $ 25,600 | $ 92,291 | $ 0 | $ 0
Pension lump sum distribution |  |  |  | 64,500 |  |  |
Pension Settlement Borrowings |  |  |  | $ 30,000 |  |  |
Group annuity contract premium liability |  |  | $ 2,000 |  | 2,000 | 0 |
Charges recognized |  |  |  |  | $ 4,000 | $ 3,900 | $ 3,300
Percentage of change in health care cost trend rate assumptions would be immaterial |  |  | 1.00% |  | 1.00% |  |
Expected long-term return on plan assets |  |  |  |  |  | 15.10% | 10.40%
Pension Benefits |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |
Employer contributions | $ 27,700 | $ 50,000 |  |  | $ 27,861 | $ 50,184 |
Pension settlement loss |  |  |  |  | 92,291 | 0 | $ 0
Defined Benefit Plan, Group Annuity Contract To Transfer Projected Benefit Obligations, Purchase Amount | $ 157,500 |  |  |  |  |  |
Projected benefit obligation to unfunded plan |  |  | $ 1,600 |  | 1,600 | $ 248,114 | $ 316,169
Settlement Funding Gap |  | $ 24,000 |  |  |  |  |
Expected long-term return on plan assets |  |  |  |  |  | 3.05% | 5.00%
Unfunded Non-Qualified Supplemental Pension Plan |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |
Projected benefit obligation to unfunded plan |  |  | 1,600 |  | 1,600 | $ 1,700 |
Charges recognized |  |  |  |  | 100 | 100 | $ 100
Other Post-Retirement Benefits |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |
Employer contributions |  |  |  |  | 423 | 476 |
Pension settlement loss |  |  |  |  | 0 | 0 | 0
Projected benefit obligation to unfunded plan |  |  | 5,712 |  | 5,712 | $ 5,726 | $ 7,370
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year |  |  | $ 100 |  | $ 100 |  |

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